Born and raised in Lakewood, Ohio, Ari's the only child of Anthony and Christina Marino. Both of her parents are researchers, her father is a gemologist while her mother is a mineralogist. They work together in studying stones and minerals in alternate forms of energy with lights and seeing how working with solar and winder energy combined to turn the refracted light into energy. They traveled a lot, taking their little girl with them from Myanmar in Indonesia to Congo in Africa. They had her tutored on flights and in hotel rooms while they went to find the right particles and gemstones that have the perfect refracting light. Nothing seemed to work, but they always tried, sending investors prototypes and seeing what can work and what needed improvement. Little Ari always tagged along since she was able to walk. Nothing stopped her since she had her father's stubborn Italian blood coursing through her veins, her brother on the hand would just stay in the hotel or at a nursery since he was still very little.
When she was 11, Ari's parents took a trip to the Blood Diamond Mines in Zimbabwe, Africa. Her parents warned her to not venture too far while they went to see some mineral deposits that surrounded a southern cave length that had been picked clean of diamond a few years ago. They weren't interested in the diamonds, but the deposits that the diamonds were surrounded by working on some scientific methods. While they walked into with a local as the guide, Ari - being the average hyperactive 11-year-old - walked a little north of the cave, leaving her baby-sitter alone (who was more interested in watching paint dry) wondering of any pretty rocks would be lying around. And in luck she saw something shimmer from inside a cavern, but getting up to the spot she saw that nothing was there. As if it vanished.
Disappointed, Ari started to head back down to the mouth of the cavern and to her napping sitter when a low rumble came from her feet as a cave-in happened, trapping her inside the cave. Her baby-sitter opened her eyes to see that Ari was missing. Her parents vacated another part of the cave and a formed a search party to find Ari. They yelled at and scolded the girl for letting their only daughter run off alone. Poor Ari was screaming and crying in the dark of the cave, using her iPod as her only light source to try and pry any rocks free to no avail. The light source she had was dying slowly, making her panic and wander away from the wall of rubble, in hopes of finding a way out. She wanted to give up hope as her iPod blinked off and left her stuck in the dark. She belted out a scream in total fear and clung to a wall, sobbing and giving in. She cried in the dark until a bright blue light illuminated from another part of the cave, catching her attention. She got up and followed it with desperate hope; the mysterious light led her to a room of bright blue and white gemstones. They weren't diamonds, they don't glow, right? She found a big one to use as a light, tying it around her neck with a string from her shoelace. She hugged it tight, admiring the glow as friendly company.
Ari stuffed a couple of handfuls of these gems into her pockets, keeping them as souvenirs for if she escaped the cave she'd have something to remember. She walked down another part of the cave until something echoed ahead of her. Voices, they were crying in anguish and sounded like they were beckoning for something or someone. Ari's heart leapt as she ran to the voices, crying until she reached the same wall of rocks that blocked her way. She cried and cried to the voices, hearing muffled responses of joy. Both Ari and her parents clawed and pulled at the rocks until Ari saw light and reached her hand through that both of her parents grabbed to. The locals helped clear the wall and pulled little Ari out from the cave and handed her to her parents. The family embraced and her parents took the next flight home to Ohio, not wanting to have their daughter go through something like that ever again.
Ari kept the gem from the cave around her neck every day, even sleeping with it to keep that "savior" close to her all the time. Little did she know that the gems she took (and hid in her closet) were Ghost Gems.
Four years passed since she got the Gem, effects of being exposed to it were starting to appear, but were not that noticeable. Examples would be like if she's sleeping she'd fall through her bed and sleep on her couch, blaming that she had sleepwalked or that she fell asleep there in the first place. It was when she was 14 and it was Halloween that her real powers came to her. She was trick-or-treating with her 7-year-old brother, taking him through the neighborhood and let him go up to a house by himself for the first time up a driveway not that far off and always in her view. She turned and her necklace got caught on a mailbox post and it ripped from her neck and fell to the ground. The gem shattered on impact and its glow was lost. In a frantic motion to save her gem, Ari picked up the pieces and held them in the palm of her hand but suddenly flinched and tried to throw away the pieces in pain. They were sinking into her hand! They burned as they entered and she couldn't stop them while they embedded into her hands and something changed into her body. Her eyes flashed to a pale blue and her hair turned jet black. She panicked and pretended to act natural, thinking that she couldn't worry about this now while her neighbor's son returned with the candy. She acted natural, letting Joey think she just changed into a costume for Halloween.
She returned home went straight upstairs and looked into the mirror, seeing her eyes and hair in shock. She closed her eyes and opened them, thinking it was a bad dream. Nothing. She hit the wall, shaking her head, wishing to look normal again and suddenly in a flash of blue light she was back in her normal colored eyes and hair. She didn't know what happened but didn't want to know. She slowly learned that something happened with the Gem in her hands, looking at old African folklore how people would have these Gems in their bodies and suddenly appear as if supernatural. She looked at what she could do, float (barely) stick her hands through stuff, and make parts disappear. But she had no control. But one day she searched through more old stories and saw that with the power of these gems came a needed "control panel" as they put it. So she tried to see if any of the remaining Gems would work and put one more around her neck, it was a little smaller than the master one, but got the job done. For a few months she tried to get her powers to work until she learned she can turn any rocks into gemstones or a different kind of mineral (since gems are just condensed minerals or a reaction of time and pressure on minerals). She hid this from her parents. Keeping it quiet and just to herself.
Her mother and father shortly divorced before her 15th birthday, arguing about new power methods and her mother left, moving to New York with her little brother Joey, while her father looked at other places to work. Someone called him and hired him in Amity Park, thus he moved there with Ari, working now for the 'Guys in White'. They needed for recreating the Reality Gems. Ari hated this new town and had to go to regular school now at Casper High School since her father believed she didn't need tutors anymore.
Here she met her newest friend Mina one day in math class, who invited her to a study group that a senior was hosting. When she went to the group she met Tucker Foley, who welcomed her to the high school. She eventually clung to him – seeing him as a guide and shield (weak, yes she is) because she was never bullied when he was around. He introduced her to Danny and Sam (dating yes, but the Disasteroid never happened here). They shook hands, but Danny felt something when he met little Ari.
A few months passed (Ari still trying to teach herself some control) and she was always with the three as a tag-along. Sam thought it was funny to have a freshman as their shadow and Tucker agreed, Danny on the other hand wanted nothing to do with her. She had a presence that sent off his ghost sense, but yet she was completely human around them (she never transformed unless in her room, home alone). It was a night when Tucker invited Ari to Sam's place for a homework night; she needed help with math so it worked out with him. While working she went to go get something to drink and Danny talked to Tucker and Sam, explaining he didn't feel right about her. Ari returned but stopped when she overheard Danny and hid, behind a wall, turning invisible to conceal herself.
Danny's ghost sense was triggered and his eyes flash green, he knew something was wrong with her and transformed into his ghost half, telling Tucker and Sam that she was just a ghost hiding among them. Tucker said there was no way, Sam agreed with Danny – he's never been wrong about ghosts before. Ari was shocked that there was someone else like her, but stayed invisible, she was afraid of Danny. Danny flew up to go find Ari, passing by her but Tucker and Sam ran on foot after him and Sam bumped into Ari and they both fell back, Ari appearing in front of them all. She pleaded with Danny she wasn't a complete ghost like he assumed. He didn't believe her and she had to show him, Sam, and Tucker her true form, transforming into her ghost half. The gang was astounded that there's another halfa like Danny in the world. She turned back into human form and backed herself into a wall, tears running down her face.
Danny's anger subsided – he knew how she felt. He knew she was scared and turned back into his human form, apologizing for lashing out. Tucker welcomed her to the gang officially. She explained to them how her father works for the Guys in White and how Ghost Hunters are always around and she hides in her room, never getting to train herself to control her powers. Tucker offered the idea of Danny helping her. Danny was hesitant but then finally agreed. Now she hangs with them, practicing when she can at the Fenton's home in the basement with Danny. She hangs out with Mina, but she doesn't know her secret and neither does her father, mother, or brother.